This invention relates generally to manufacture of plastic packaging bags. More particularly, this invention relates to separating and partially separating bags within a perforated chain of bags.
In the field of packaging articles such as food products, it is known to load the products into plastic bags, and then to seal the bag openings, respectively. It is also known to carry out the sealing operation in a vacuum chamber where the residual atmosphere within the bag can be withdrawn and the package sealed under vacuum conditions in order to avoid deterioration of the food product in the sealed bag.
It is known to load product articles into packaging bags, made of flexible heat shrinkable film material, by supplying bags to a bag loader, in the form of a continuous chain of discrete bags carried releasably on adhesively-coated support tapes. Articles to be packaged are situated at a loading station typically by feeding on a conveyor belt into a guide from which the article is loaded into the leading bag of the chain, after opening of the bag for example by an inflation air jet. The bag loader accepts the bags in shingled or imbricated configuration, and it is then left up to either the operator or some article-advancing means, to remove the top loaded bag from the imbricated bag chain before the next successive bag can be inflated and loaded. Supplying the bags in imbricated configuration in a taped chain offers considerable advantages over supplying the bags one at a time to the loading equipment.
The present invention aims to provide means for making a packaging system which is capable of more rapid and economic operation for loading articles into bags which are fed to a loading station in the form of a sequence of bags. Such system is intended to enable the packaging operation to be speeded up in subsequent vacuumizing and sealing steps as well.
U.S. Pat. Nos. 3,161,347 and 3,331,182 disclose of typical bag loading processes and apparatus and illustrate the use of a chain of bags in imbricated form supported on a continuous support member so that the imbricated bags arrive at a loading station where the uppermost bag is pneumatically inflated and has a product article placed therein, after which the bag is removed from its elongate support member and delivered ready for subsequent advance to a bag closing station.
U.S. Pat. No. 3,587,843 discloses a package of such bags supported on two adhesively coated tapes to which the bags are releasably attached. The manufacture of such a package of taped bags requires initially the production of a plurality of separate bags, then the shingling of those bags on a moving delivery conveyor accompanied by superimposition and pressure adhesion of the tapes thereto after which the taped bag supply can be packaged either by being wound up on a support roll or layered into a box. The package of bags, either on a support roll or in a box, or on or in any other suitable holder, can then be transported to a user location where the individual bags will be filled by a bag loader to which the bags are fed as a chain of imbricated bags.
Of general interest is the disclosure of U.K. patent application No. 2,078,654A for "Loading Plastic Bags for Packaging Purposes" published Jan. 13, 1982, directed to a packaging process that utilizes a chain of side-sealed packaging bags with the mouths of the bags facing laterally of the chain of bags. Several of the bags are loaded in a batch, and the bags are subsequently closed in batch-wise fashion.
Of general interest is the disclosure of U.K. patent application No. 2,080,179A for "Apparatus for Separating and Loading Bags of a Chain of Side-Sealed Packaging Bags" published Feb. 3, 1982, directed to a mechanism for separating and loading bags from a perforated chain of side-sealed laterally extending packaging bags, especially in connection with the preceding cited packaging process.